Airless paint spray equipment has found considerable commercial acceptance over recent years. Because of the design of such equipment, paint being discharged from the spray gun may range in pressure from 2000 psi to 5000 psi, depending upon the type of nozzle used and the viscosity of the material being pumped. Paint under pressure in this range can be extremely dangerous to personnel in the immediate area of spraying because since it may easily penetrate and damage living tissue.
This has given rise to the need for safety devices to prevent the accidental discharge of high pressure paint from airless paint spray guns. While safety devices have been provided for many types of hand lever operated tools and other equipment, they are not suitable for the present airless paint spray gun, nor do they provide the degree of safety required for this high pressure application.